Sprinkler systems

[mshields]

When we do work in an existing building, our Fire Protection department either turns the heads up (in which case we do not need to provide heat detectors) or they disable the sprinkler in that area and we do provide temporary heat detectors.

1. Why is it that in some instances we can turn the heads up and others we can't.

2. What problem does turning the heads up solve?

3. How can it be that turning them up provides adequate coverate. Doesn't this potentially make the distribution of water below the heads uneven. i.e. with various obstacles above the ceiling, one would expect a less even spray falling back down into the space.

4. If you're putting heat detectors in, do you have to necessarily disable the sprinklers in that area? Or do the sprinklers remain active with the heat detectors therefore providing supplimental protection. Or perhaps the heats are providing primary protection and the sprinklers are providing sort of a "Can't hurt" redundancy of protection.

4. Proceedurally, how does one switch from the sprinkler coverage to the temporary heat detectors. Is the following correct:

a. Take down walls within space (but not ceiling)

b. Install temp heat detectors throughout the space.

c. only after temp heat detectors are installed, remove ceiling

Thanks,

Mike

 

[Coug Dad]

Turning heads up reduces the distance between the thermal detection of the sprinkler and the new ceiling above. The greater the distance between the ceiling and the sprinkler the longer time and larger fire it takes to activate the sprinkler. Sprinkler heads (SSU and SSP) are designed for either upright or pendant installation. Installing a pendant head in the upright condition will reduce its effectiveness. For temporary conditions during construction, many FD accept what is reasonably acheivable.

 

[FM William Burns]

It is based primarily on the type of ceiling construction obstructed/unobstructed that determines the use of SSU/SSP type heads in accordance with NFPA 13 [8.5 and 8.6].

Your fire protection department should be installing piping and heads based on the type of ceiling/roof construction. If the renovation affects existing piping that has pendant heads in a drop or hard lid ceiling; the ceiling serves as the construction feature allowing for pendant sprinkler use. Removal of the ceiling where an existing pendant installed sprinkler line exists, creates a distance above a pendant head sprinkler line that is not acceptable by the standard for sprinkler positioning, spacing and location. If the space above the ceiling is combustible, a typical installation would call for uprights in the space above the ceiling. Again, it’s based on ceiling/roof construction in accordance with the standard on sprinkler installation NFPA 13.

BFD most likely requires "temporary" heat detection in lieu of smoke detection in concealed spaces or areas under construction to prevent false alarms associated with renovation work. You would not disable sprinklers in any area under construction unless the construction is the sprinkler system. Heat detection in an area served by sprinklers is a redundant protection feature or associated to other features of fire protection like possibly heat/smoke removal based on the other posting.

 

[cda]

agree with everyone above

just a question who is "our Fire Protection department either turns the heads up " private sprinkler company? or in house sprinkler workers??

interesting concept, have not heard that one before

guess it would depend on how long they are working in the area, construction type, and what is going on in the area

unless there is very major remodel going on most sprinkler systems are left operational, even in the remodel area.

I guess you gain a little by putting heat detectors in the area??? someone will no the place is burning